Yeah, I agree cab. My right foot is part of the problem, but I return from a short cruise with a big smile every time. Torque is cool. My cruise AFR is 13.5 on average. Think I can clean that up with IFR and T-slot jets.
A lot will depend on fuel and carb type .
My 505 runs 13.2-13.5 @ cruise . It will hunt lean at 13.7 .
T slot changes only seem to be required on 4500 carbs .
As others have said before give the motor what it needs , dont chase the mythical number .
With my 29" street tyre , 4.1 gear and 6000 stall i cruise @ 3250 = 63mph thereabouts . Mostly our highway limits are 61mph (100kph) occassionally 65(110kph)
I get 8-9ish mpg daily 10-12ish highway . At 3500 (110kph) it all goes to #ell .
You want economy buy a Hyundai 😂
Tex